[PATCH 4/4] therm_throt: Add a cumulative event counter and export it to /sys.
From: Dmitriy Zavin
Date: Tue Sep 19 2006 - 22:43:54 EST
Signed-off-by: Dmitriy Zavin <dmitriyz@xxxxxxxxxx>
---
arch/i386/kernel/cpu/mcheck/p4.c | 3 +
arch/i386/kernel/cpu/mcheck/therm_throt.c | 114 ++++++++++++++++++++++++++++-
arch/x86_64/kernel/mce_intel.c | 3 +
include/asm-i386/therm_throt.h | 1
4 files changed, 117 insertions(+), 4 deletions(-)
diff --git a/arch/i386/kernel/cpu/mcheck/p4.c b/arch/i386/kernel/cpu/mcheck/p4.c
index 5f9896f..7d10e67 100644
--- a/arch/i386/kernel/cpu/mcheck/p4.c
+++ b/arch/i386/kernel/cpu/mcheck/p4.c
@@ -115,6 +115,9 @@ static void intel_init_thermal(struct cp
l = apic_read (APIC_LVTTHMR);
apic_write_around (APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
printk (KERN_INFO "CPU%d: Thermal monitoring enabled\n", cpu);
+
+ /* enable thermal throttle processing */
+ atomic_set(&therm_throt_en, 1);
return;
}
#endif /* CONFIG_X86_MCE_P4THERMAL */
diff --git a/arch/i386/kernel/cpu/mcheck/therm_throt.c b/arch/i386/kernel/cpu/mcheck/therm_throt.c
index 3d6f217..c56fffb 100644
--- a/arch/i386/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/i386/kernel/cpu/mcheck/therm_throt.c
@@ -2,14 +2,16 @@
* linux/arch/i386/kerne/cpu/mcheck/therm_throt.c
*
* Thermal throttle event support code.
+ * Maintains a counter of thermal throttle events in /sys.
*
* Author: Dmitriy Zavin (dmitriyz@xxxxxxxxxx)
*
* Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
- *
+ * Inspired by rossb and alb's counter code.
*/
#include <linux/percpu.h>
+#include <linux/sysdev.h>
#include <linux/cpu.h>
#include <asm/cpu.h>
#include <linux/notifier.h>
@@ -23,6 +25,44 @@ #endif /* CONFIG_X86_64 */
#define CHECK_INTERVAL (300 * HZ)
static DEFINE_PER_CPU(__u64, next_check) = INITIAL_JIFFIES;
+static DEFINE_PER_CPU(unsigned long, thermal_throttle_count);
+atomic_t therm_throt_en = ATOMIC_INIT(0);
+
+#ifdef CONFIG_SYSFS
+#define define_therm_throt_sysdev_one_ro(_name) \
+ static SYSDEV_ATTR(_name, 0444, therm_throt_sysdev_show_##_name, NULL)
+
+#define define_therm_throt_sysdev_show_func(name) \
+static ssize_t therm_throt_sysdev_show_##name(struct sys_device *dev, \
+ char *buf) \
+{ \
+ unsigned int cpu = dev->id; \
+ ssize_t ret; \
+ \
+ preempt_disable(); /* CPU hotplug */ \
+ if (cpu_online(cpu)) \
+ ret = sprintf(buf, "%lu\n", \
+ per_cpu(thermal_throttle_##name, cpu)); \
+ else \
+ ret = 0; \
+ preempt_enable(); \
+ \
+ return ret; \
+}
+
+define_therm_throt_sysdev_show_func(count);
+define_therm_throt_sysdev_one_ro(count);
+
+static struct attribute *thermal_throttle_attrs[] = {
+ &attr_count.attr,
+ NULL
+};
+
+static struct attribute_group thermal_throttle_attr_group = {
+ .attrs = thermal_throttle_attrs,
+ .name = "thermal_throttle"
+};
+#endif /* CONFIG_SYSFS */
#ifdef CONFIG_X86_64
static void therm_throt_log_mce(unsigned int cpu, __u64 status)
@@ -39,13 +79,13 @@ static void therm_throt_log_mce(unsigned
#endif /* CONFIG_X86_64 */
/***
- * therm_throt_process - Process thermal throttling event
+ * therm_throt_process - Process thermal throttling event from interrupt
* @curr: Whether the condition is current or not (boolean), since the
* thermal interrupt normally gets called both when the thermal
* event begins and once the event has ended.
* @status: Event status information.
*
- * This function is normally called by the thermal interrupt after the
+ * This function is called by the thermal interrupt after the
* IRQ has been acknowledged.
*
* It will take care of rate limiting and printing messages to the syslog.
@@ -58,6 +98,9 @@ void therm_throt_process(int curr, __u64
{
unsigned int cpu = smp_processor_id();
+ if (curr)
+ __get_cpu_var(thermal_throttle_count)++;
+
if (time_before64(get_jiffies_64(), __get_cpu_var(next_check)))
return;
@@ -66,7 +109,9 @@ void therm_throt_process(int curr, __u64
/* if we just entered the thermal event */
if (curr) {
printk(KERN_CRIT "CPU%d: Temperature above threshold, "
- "cpu clock throttled\n", cpu);
+ "cpu clock throttled (total events = %lu)\n", cpu,
+ __get_cpu_var(thermal_throttle_count));
+
add_taint(TAINT_MACHINE_CHECK);
#ifdef CONFIG_X86_64
@@ -75,5 +120,66 @@ #endif
} else {
printk(KERN_CRIT "CPU%d: Temperature/speed normal\n", cpu);
}
+}
+
+#ifdef CONFIG_SYSFS
+/* Add/Remove thermal_throttle interface for CPU device */
+static __cpuinit int thermal_throttle_add_dev(struct sys_device * sys_dev)
+{
+ sysfs_create_group(&sys_dev->kobj, &thermal_throttle_attr_group);
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static __cpuinit int thermal_throttle_remove_dev(struct sys_device * sys_dev)
+{
+ sysfs_remove_group(&sys_dev->kobj, &thermal_throttle_attr_group);
+ return 0;
+}
+
+/* Get notified when a cpu comes on/off. Be hotplug friendly. */
+static __cpuinit int thermal_throttle_cpu_callback(struct notifier_block *nfb,
+ unsigned long action,
+ void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ struct sys_device *sys_dev;
+
+ sys_dev = get_cpu_sysdev(cpu);
+ switch (action) {
+ case CPU_ONLINE:
+ thermal_throttle_add_dev(sys_dev);
+ break;
+ case CPU_DEAD:
+ thermal_throttle_remove_dev(sys_dev);
+ break;
+ }
+ return NOTIFY_OK;
+}
+static struct notifier_block thermal_throttle_cpu_notifier =
+{
+ .notifier_call = thermal_throttle_cpu_callback,
+};
+#endif
+
+static __init int thermal_throttle_init_device(void)
+{
+ unsigned int cpu = 0;
+
+ if (!atomic_read(&therm_throt_en))
+ return 0;
+
+ preempt_disable(); /* CPU hotplug */
+ for_each_online_cpu(cpu) {
+ /* connect live CPUs to sysfs */
+ thermal_throttle_add_dev(get_cpu_sysdev(cpu));
+ }
+ preempt_enable();
+
+ register_hotcpu_notifier(&thermal_throttle_cpu_notifier);
+ return 0;
}
+
+device_initcall(thermal_throttle_init_device);
+#endif /* CONFIG_SYSFS */
diff --git a/arch/x86_64/kernel/mce_intel.c b/arch/x86_64/kernel/mce_intel.c
index a13096e..7bbcfbb 100644
--- a/arch/x86_64/kernel/mce_intel.c
+++ b/arch/x86_64/kernel/mce_intel.c
@@ -76,6 +76,9 @@ static void __cpuinit intel_init_thermal
apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
printk(KERN_INFO "CPU%d: Thermal monitoring enabled (%s)\n",
cpu, tm2 ? "TM2" : "TM1");
+
+ /* enable thermal throttle processing */
+ atomic_set(&therm_throt_en, 1);
return;
}
diff --git a/include/asm-i386/therm_throt.h b/include/asm-i386/therm_throt.h
index c6e638b..4cf4f75 100644
--- a/include/asm-i386/therm_throt.h
+++ b/include/asm-i386/therm_throt.h
@@ -3,6 +3,7 @@ #define __ASM_I386_THERM_THROT_H__ 1
#include <asm/types.h>
+extern atomic_t therm_throt_en;
void therm_throt_process(int curr, __u64 status);
#endif /* __ASM_I386_THERM_THROT_H__ */
--
1.4.2
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/